We are involved in studying the structure and regulation of eukaryotic genes, using Drosophila as an experimental object. Although we come from diverse backgrounds, (genetics, molecular biology, development biology, population genetics), we intersect in our common interest: to use the genetically most favorable higher organism, Drosophila, and the current techniques of cellular and molecular biology, to illuminate how the genes of higher organisms are organized, evolve, and are regulated during development. Indeed, a strength of our group is that it represents complementary and yet overlapping approaches. In the context of a program project, we intend to: (a) Analyze by molecular and genetic means the mechanisms regulating the orderly production of chorion proteins during oogenesis. (b) Study in vitro transcription of chorion and ecdysteroid-induced genes, and the regulation of the latter by steroids. (c) Analyze by molecular and cytogenetic techniques an interesting chromosomal region, 71C-E, which encompasses ecdysteroid-induced genes. (d) Develop techniques for somatic cell genetics, using continuous cell lines of defined genotype. (e) Study by molecular and genetic techniques the choline acetyltransferase gene and possible regulatory mutants affecting its expression. (f) Study genetic polymorphism by sequencing the alcohol dehydrogenase gene of isogenic lines derived from four natural populations. (g) Study the nature of large transposable elements.